The present invention relates generally to cleats or calks for use on the soles of boots and the like, and more particularly to a novel cleat or calk which provides improved gripping and longer life over prior cleats and calks.
It is a common practice to enhance the ground gripping characteristics of numerous types of footwear through the mounting of cleats, spikes or calks on their soles. The ground gripping characteristics of certain sporting event shoes, such as golf shoes, are conventionally improved by mounting conical spike-like elements on the soles. The spikes generally have threaded shanks which enable releasable threaded mounting in receptacles or anchor inserts secured to the soles in spaced patterns. Similar type spikes have been employed with mountain climbing boots and boots used by loggers, forestry workers and hunters.
A significant drawback in the use of known spike-type grip enhancing devices on boots and the like, and particularly boots such as loggers boots which undergo rigorous use on various terrains including rocks and logs, is that the spikes undergo relatively rapid wear and lose their gripping characteristics, thus requiring relatively frequent replacement or maintenance. The reduction or loss of gripping ability also greatly diminishes the safety factor expected from use of the spikes. Moreover, in the case of logging boots, a substantial number of the spikes, such as thirty or more, may be mounted on a single sole. The cost of replacement or maintenance of the spikes can therefore be quite significant.
In the case of logging boots, attempts to address the aforedescribed problems encountered with spike-type cleats or calks have included the mounting of tricounies along the edge of a sole which also has conical spike-type calks mounted thereon. The tricounies have toothed or serrated edges which dig into the wood or bark of a tree and further enhance gripping with attendant improved safety. Again, however, the use of tricounies leads to increased cost without significantly increasing the wear life of the associated spike-type calks. Accordingly, a cleat or calk having improved gripping and wear life characteristics would result in greater safety and economic efficiencies than experienced with known cleats and calks.